Conventional low power systems including a graphics processor, such as system 100 shown in FIG. 1, utilize a low power graphics processor 140 which reduces power usage at least in part by reducing graphics data processing performance to compared with other graphics processors. System 100 includes a host processor 120, a main memory 110, and a chipset 130 which is directly coupled to graphics processor 140. Graphics processor 140 receives instructions and data from chipset 130. Graphics processor 140 processes the data, storing image data in frame buffer 145 for output to a display 170.
High performance graphics processors offer greater graphics processing throughput which contributes to increased power usage compared with a low power graphics processor, such as graphics processor 140. The increased graphics processing throughput may be achieved by operating at a higher clock rate, including two or more graphics processing pipelines, and using wider and/or faster internal and external interfaces. The higher performance graphics processor is implemented in a larger die size than graphics processor 140 in order to include more transistors. Even when a high performance graphics processor is not processing graphics data it contributes to overall system power consumption due to the static power resulting from transistor leakage. Therefore the static power of a high performance graphics processor is greater than the static power of a low power graphics processor. Consequently, high performance graphics processors are not used in conventional portable systems which are battery powered.
Accordingly, it is desirable to minimize overall power consumption while improving graphics processing performance.